Pitch problems

[ArtD]

I recently purchased a Juki 1341 from a highly regarded dealer who advertises here, and the machine runs exceptionally well except in the case of sewing waxed canvas. Although I get an even pitch with all other materials (including a single sheet of copier paper) in all thickness and at all stitch lengths, the stitches in waxed 12 ounce canvas vary on an irregular basis. This happens whether I am using thread or not and whether I am sewing multiple layers or a single layer. I’ve check adjustments and they all seem spot on. Hoping someone here might have a suggestion of how to address this.

I know I’m not sewing leather, although waxed canvas is often compared to leather.  My apologies if this is an inappropriate post.

Art

 

 

 

 

yy

[DieselTech]

Are you using a round point or a ball point needle for the canvas? 

Also what thread size & needle are you using? & what needle point style?

Thanks. I am a newbie with machine sewing & I been sewing some canvas too, but with a Cobra class 26.

 

[ArtD]

I’m using a 19 round point needle with 92 thread.

Let me add that I’m also disappointed with how it climbs compared to my 1508 flatbed. Maybe my expectations are too high.

Edited December 13, 2024 by ArtD

[DieselTech]

20 minutes ago, ArtD said:

I’m using a 19 round point needle with 92 thread.

Let me add that I’m also disappointed with how it climbs compared to my 1508 flatbed. Maybe my expectations are too high.

Are you using a smooth feed dog & smooth presser foot? Or are you using a serrated feed dog & presser foot? 

There will be some professionals come along shortly, I bet they can give you the right answer.

[ArtD]

I’m using the standard feed dog and a smooth walking foot, the same as on the 1508.

[Northmount]

2 hours ago, ArtD said:

I’m using the standard feed dog and a smooth walking foot, the same as on the 1508.

Increase the presser foot pressure probably because the waxed canvas is somewhat slippery.

[kgg]

5 hours ago, ArtD said:

I’m using a 19 round point needle with 92 thread.

Beside what @Northmount has suggested I would move up to a #20 or #21 needle. I think that the thread is being caught by the canvas and there also maybe a very slight build up of wax on the thread which maybe adding to the problem. The canvas maybe being drawn down into the feed dog hole which can cause problems if that is the case you may have to put a piece of regular writing paper on the feed dog side and tear it off after.

Even though canvas is a fabric sometimes you may have to go with a leather point needle so I would do a test seam and see if that solves the problem.

Also what stitch length on your seam are you trying?????

kgg

[ArtD]

I’m set at a 4mm stitch.

I read the engineering manual and compare the 1341 to the 1508 sitting next to it and have the following observations.

1. the feed dog sits below the needle plate when the walking foot makes contact.

2. The top feed would seem to be out of adjustment. The needle, walking foot and top of the needle plate are all supposed to meet at the same point when certain pre-conditions are set. They meet, sort of, when the walking shoe makes contact with the feed dog below the needle plate. If I align the walking foot and the outside feet at the needle plate, the needle is nearly 3/16” above this.

My question for anyone who knows, if I adjust the top feed, do I need to also adjust the timing?

 

Thanks.

Art

[ArtD]

Now I’m really confused. I checked both the feed cam timing and the top feed cam timing against the engineers manual that I downloaded from here and my machine isn’t even close to either standard setting. I didn’t actually make the adjustments but was able to make as assessment based on the manual indicating the position of certain screws when properly adjusted. 

And yet it works, although I still have the pitch problem. Is it possible the engineers manual from Juki has changed in recent years. What am I getting wrong here?

Thanks.

Art
 

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